Friction clutch



March 25, 1930.

J. GLISCH FRICTION CLUTCH Filed May 28, 1927 INVENTOR. M

AKTTORNEY.

' engagement with the arms'has been enormous of my clutch spider showingthe mounting 70 Patented Mar. 25, 1930 I 1,751,809

UNITED STATES PATENT OFFICE JOHN F. GLISCH, F MILWAUKEE, WISCONSINFRICTION CLUTCH Application filed my 28, 1927. Serial No. 194,933.

My invention relates to improvements in provide a clutch which will besafelyoperfriction clutches with particular reference able both byreason of the absenceof projecto clutches of that type in which a"clutch tions which might catch the clothing ofthe ring is expandedwithin a ring or rim for operator and by reason of the ease'andposigripping purposes and released for contractiveness of its releasedue to the shape and 55 tion under its own resilient tension to itsstructure of the expanding and contracting normal diameter t mechanismof my device; a

It has been well known practice in the In the drawings: manufacture ofclutches to provide an arm, Figure 1 is a longitudinal axial section ofor a plurality of arms, the ends of which are my clutch mechanism.

covered with friction material, said arms 1 Figure 2 is a front view-ofthe actuating being so designed as to be radially extensible mechanismof my clutch on a section through for friction engagement with opposingparts line 22 of Figure 1 and showing a port-ion of the clutchmechanism. It has also been of one of the arms cut away to exhibit thegeneral practice to provide a cone shaped colmounting of one of thedogs.

, lar slidable onthe shaft for thrusting these 'Figure 3 is a detailview of one of the dogs. armsradiallyintoengagement. Insuchmech- Figure4: is an isometric View of the split anisms when the clutch is released,the power friction ring which forms part of my device. requiredheretofore to slide the cone out of Figure 5 is a radial view of one ofthe arms and in many cases prohibitive. This difof the dog. ficulty isdisengaging clutches of this gen- Like parts are identified by the samereferalcharacter is generally due to the posierence charactersthroughout the several tioning of the various parts ,overcenter andviews.

' in a position which substantially locks the Mounted upon thedrivenshaft 1, I have 7. parts against retraction. provided an armedspider 2, which is secured The primary objectof'my invention is to .tothis shaft in any suitable manner; In the provide aclutch of the abovementioned type drawings, I have shown it vsecured to the with meanslforutilizing the principle of the vshaft 1 by means of a set screw 3. Eachof wedge for expanding or clutch setting purthe arms is-recessed at 4 toprovide anchorposes, and theprinciple of the lever for reage for thelugs 5, which extend-radially-inleasing purposes whereby the reliabilityof wardlyfrom' the annular split friction, ring a cone expander actingupon radial arms or orjclu'tch member ,6, which is adaptedto endogs maybe combined with the ease ofrecompass the entire driven mechanism. -TheTF5 lease characteristic of lever mechanisms. members thus far describedwill, therefore,

Afurther object of my invention is to pro-- rotate as a unit by reasonof the engagement vide a clutch setting oscillatory dog-which oftheselugs 5 the recesses ofthe spider is adapted forsubstantially a linecontact arms, 7 y 1 f; with the actuated clutch member, the line of Eachof the-spider arms has axial extenil'il contact being substantiallyparallehto the 'sions7 spaced from the shaft1,-and each of ac axis aboutwhich the dog oscillates and the these extensions is channeled ,atS toform a q dog being oscillated by an actuating member radially extendingpath for the liinitedremovable along a line transverse to said axis Iciprocationof dogs or eccentrics '9. Each of which holds the dog inunstable equilibrium these dogs or levers is provided with fulagainstthe associated clutch member when crum trunnions lOwhich are journaledloosef in clutch setting position whereby the initial ly in .theopengrooves 11 formed in the sides retractive movement of the actuatorinstantof the channels, An adjustment screw 12 ly tilts the dog anddisplaces it from its posiwith a lock nut 13 is provided for each oftion of line contact with said clutch member; the, dogs 9, as. shown inFigure 3, and each It is a further object of my invention to of the dogsis mounted in the grooves 11 with Bet its adjustment screw adjacent theshaft which forms the support or mounting for the parts thus fardescribed. A clutch control cone or eccentric actuator 14, whichcomprises a wedge slidably mounted on the shaft 1, is provided with ashifter groove 15 and a curved face 16 which, when the cone is forcedalong the shaft, is thrust against the heads of the adjustment screws12, thereby to force the dogs or eccentrics 9 outwardly against thesplit ring 6.

The parts thus far described may constitute the driven elements of theclutch mechanism. The driving elements comprise a shaft 17 and a pulley18 which is provided with an axial annular flange 19 and a hub 20. Theusual form of belt drive, as shown at 21, may, of course, be substitutedby a gear drive if the face of the axial flange 19 is cut to provideteeth in the usual form of gear construction.

The shape of the lever dogs 9 is important in the operation of mydevice. The face of each of the dogs 9 is curved and cut away to form aneccentric shoulder or lobe, as shown at 22, and the rear outwardlyprojecting corner is .cut away to form a curved face 23. By mountingthese dogs, as shown in the drawings, I have provided for expansion ofthe split friction ring as follows:

The engagement of the clutch is accomplished by axial thrusts of thecone 14: with its curved face 16 under each of the adjustment screws 12in such manner that the dogs or eccentrics 9 are first forced inwardlyabout trunnions 10 to the radial alignment indicated in Fig. 1 and thenmoved bodily radially outwardly in their channel mountings, as permittedby the formation of the trunnions and their guideways. The split ring isthereby expanded to engage the inner face of the flange 19 of thedriving pulley, and motion is thereby transmitted from the drivingpulley through the split ring which, by means of its lugs 5 in therecesses 4 of the spider arms, drives the connecting shaft 1. V

v Release of a clutch, which has been in operation and which hasheretofore presented difficult problems by reason of the usual lockingof the parts in their engaged position, is easily accomplished in my newdevice A in the following manner:

.When the cone 14 is retracted from the clutch mechanism, the initial"axial movement thereof draws with it frictionally the set screws 12which force the pivoting of the dogs 9 as levers upon their trunnions10. This initial movement immediately relieves the split friction ring 6from pressure by the dogs for the curved faces 22 will be instantlyretractedfrom the ring6, and the clutch will be released. Usual lockingof the clutch in engagement is thus overcome. It will be found thatclutches embodying my improved construction require very little powerfor their release.

I have formed my split ring of soft iron, but it will be readilyunderstood that the face of the split ring may be covered with frictionmaterial in any one of the several ways now common in the building ofclutches. As will beapparent from Figures 1 and 5, the surfaces or facesof the spider'2 between the arms or axial extensions 7 act as stops forthe dogs 9 limitingthe extent of the oscillatory movement of the dogs inthe direction of theirengagement with ring 6.

I claim: V

1. The combination with clutch members having opposed friction surfaces,of driving connections carrying one of said members, driven connectionscarrying the opposed member, a channel member providing a slottedguideway, a reciprocable block provided with pivot pins receivable insaid slots, said block having a curved working face adapted, in oneposition, to engage one of said members, and means for forcing the blockalong the guideway into said position,

said block being adapted to bodily retract,

and to simultaneously oscillate away from the engaged member.

2. In a clutch. the combination with a driving member and a drivenmember, of a friction ring adjacent to and frictionallyengageable withthe driving member and mounted for rotation with the driven member, aradial arm extending toward the friction ring from the driven member,said radial arm being carried by the driven member, a dog'eccentricallyand pivotally mounted on theradial arm, and a wedge adapted to adjustthe dog to present its longer radius against the ring and to moveit'bodily into pressure engagement therewith.

3. The combination with rotatable concentric members, of an interposeddog mounted for radial movement into contact with the outer of-saidmembers and also'connected with the inner member for rotation therewith;said dog being adapted totilt. in a direction to instantly release itsengagement with the outer of said members,and'1neans for adjusting saiddogradially and engageable with the latter for" tilting movementthereof. r V I 4. An expanding clutch including a' set of radiallymovable dogs having outer faces eccentric in axial planes, said'dogsbeing tiltable in said planes and adapted to present their eccentricfaces at a decreased radius when tilted in one direction, and an expander adapted to adjust said dogs radially with their longer radiipresented for clutch setting operation, and to tilt the dogs to presenttheir shorter radii to the work when the expander moves retractively. Y

An expanding clutch including opposed friction members and radiallymovable dogs provided with trunnions, a spider providing journalssupporting said trunnions and providing channels within which said dogsare radially reciprocable, a stop limiting pivotal movement of the dogson the trunnions in one direction, and an expander adapted to force thedogs outwardly radially in engagement of the clutch and to swing thedogs on their trunnions in release thereof.

6. In a clutch the combination -with a clutch member movable radially ofthe clutch, of an eccentric movable radially independently of andengageable with said member, and an eccentric actuator arranged, whensaid clutch is rendered operative, to first place the eccentric with itslobe in its axially relative position of operativeness and to then movesaid eccentric radially, whereby to cause said member to move radially,said actuator being arranged also, whensaid clutch is renderedinoperative, to rotate said eccentric for release of said member.

JOHN F. GLISCH.

